Java Essentials - Variables in java

In this video we are discussing variables in Java

So what are the different do's and don'ts while declaring a variable

We'll be discussing them in our video. So a variable is nothing but one identified of the memory location or storage area to hold data

and each variable should have a unique name to identify different data

We know that variable nomenclature must be very much purposeful. Depending upon the purpose of the variable declaration, the nomenclature or the naming of the variable should be done accordingly

Let us suppose that is one variable which is nothing but one

identified which will be holding the value of the sum of a series. Then in that case the variable name should be given, say, a variable, say, A B, C, or say, count, or whatever you prefer best, that should be given. A variable in that case should not be giving a name like, say, A, B, C, or say, count, or

or say value so that should not be the good practice so variable naming is a very important thing variable naming and also the function naming so that has to be done purposefully and that is

falling in the best programmers practice so depending upon the data type of

the variable some memory space some storage will be occupied against the variable

and the variable naming should be done perfectly and purposefully so here is

some syntax to declare variables in Java say i nt my variable you can find that this variable name is preceded by the by the prefix that is the

mine so that it means i have defined this variable and this variable is having the data type iant in case of java

for the i nt 4 bytes of memory space is getting occupied that means against this my variable

32 bits of memory space will get occupied and accordingly it can hold the range of the values

accordingly so that's why the variable name is not nothing but one identify name depending upon the data type the stores the storage space

which is going to get occupied in the memory that will be decided so my variable is equal to 10 So I initializing my variable with the value 10 here So we can directly assign values after declaration like this one

So I ent my variable is equal to 10. So instead of writing these two lines separately

I can put the whole thing in one line. So declaring the variable and also initializing with

with some value as we have put that one on the right on side of this equal to operator. So there

some rules for naming the variable so let us go for some do's and don'ts what are to be

followed and what are to be avoided so my variable is a valid variable name so it is okay

for us then we can go for underscore my variable so that is also valid but it is not a good

name to be used here but obviously you can do it you can go for say my then blank space so

blank space should not be allowed in our variable name you can go for this proper type of

So M small letter and V capital in this way we can go for say mine series sum mine all in the lower case series S capital and then some S capital and all other letters will be in the lowercase That is a good programmer choice and practice and best practices will be there

And so, but a variable name cannot, cannot, cannot take a blank space as it's one of the characters

So that's why it is invalid. My variable one is valid. Yes, you can go for the numeric digits can be put in the variable name, but a variable

name cannot start with a digit. it can start with some alphabet or underscore we can have this dollar my variable which is

also valid but should not be used so that is our session and you can go for this variable

then single quote or a double quote you can give in between and that is also invalid here

so depending upon the purpose of the variable the variable nomenclature has to be decided and then

depending upon the data type of the variable how much storage space is going to get

occupied during the runtime of the Java application that will be decided so in this

video we have discussed what is a variable and how to define a variable in case in

in case of Java programming thanks for watching this